MRI Compatible Fiber Optically Sensorized Biopsy Needles for Oncological Applications Intelligent Fiber Optic Systems Corporation (IFOS) 2363 Calle del Mundo, Santa Clara, CA 95054-1008 www.ifos.com PROJECT SUMMARY/ABSTRACT (MAXIMUM 30 LINES) Minimally invasive procedures, including biopsies of hard tumors, rely on advances in miniaturized tools and robotic assistance to reduce trauma to patients and speed healing times. However, present tools lack the real- time position awareness that surgeons use to an advantage in open surgery. In this Phase I SBIR proposal to the National Cancer Institute (NCI), IFOS, in collaboration with an interdisciplinary team at Stanford University, proposes to demonstrate real-time needle shape determination as a basis for needle tip tracking, as well as downstream applications for steerable needles. In particular, IFOS and team members aim to develop and test magnetic resonance imaging (MRI)-compatible, optical fiber-sensorized, biopsy needles using real- time needle shape information superposed on MRI images to visualize the intervention area. This addresses the growing interest towards interventional MRI procedures, such as biopsies, ablations, and cryosurgeries performed under continual MR scanning. In particular, the ability to guide biopsy of abnormalities seen on cross-sectional imaging studies is well recognized as an efficient and effective means of achieving a tissue diagnosis, and MRI provides a number of significant advantages over other imaging modalities, all the more so with the advent of new long lived contrasting agents that can only work in tandem with MRI. Preliminary work by the team has already indicated the potential of integrating miniaturized fiber optic (FO) force and deflection sensors based on optical fiber Bragg grating (FBG) technology into robotic tools for shape sensing and force feedback. Fiber optic techniques are especially suited for instrument manipulation within MRI systems due to their immunity to electromagnetic interference (EMI), bio-compatibility and superior robustness as compared with conventional strain gauges. The proposed project aims to demonstrate 3D, high-density integration of FBG sensor arrays into robotic tools such as biopsy needles to provide visual needle path tracking and manipulation in real-time. During Phase I, sensors multiplexed along optical fibers will be embedded into ultrathin biopsy needles and used to determine the entire needle bend shape, including the needle tip position, for MRI-guided biopsy procedures. The 3D needle profiles will be annotated over MR images acquired intraoperatively. Testing will be performed on phantom objects mimicking liver tissue. Liver is chosen as an organ subject due to the high need to reduce positional error and minimize multiple needle passes, thus improving clinical outcomes. This is especially the case in patients susceptible to excessive bleeding, e.g., perihepatic bleeding due to underlying liver disease. As a secondary objective, preliminary designs will be developed to include tool maneuverability, which will be carried into detailed in-vitro and animals studies used to lay out pre-clinical testing and commercialization analysis during Phase II. PUBLIC HEALTH RELEVANCE: This research aims to add miniature fiber-optic shape and force sensors to biopsy needles in order to enhance the precision, safety and efficacy of diagnostic biopsy and minimally invasive surgical procedures on liver tissue (exploiting the breakthrough sensitivity of reduced diameter biocompatible fiber sensors to enable increased success rates and patient comfort, and reduced bleeding complications by precision targeting (reduced need for multiple needle insertions) of suspected tumors, for example, with sensorized needles that are ultrathin (create smaller holes)). During Phase I, design feasibility will be demonstrated for a system that includes working sensors and related image processing and needle steering concepts, applied to phantom livers, with the work extended to more advanced in vitro and in vivo work during Phase II, culminating in a prototype MRI compatible, physician- controlled needle system for image-guided liver procedures. The proposed work will advance the field of intelligent needle development for robotic surgery tools with potentially broad-based spin-off applications for both oncological and non-oncological medical fields.